github.com/ebitengine/purego@v0.8.0-alpha.2.0.20240512170805-6cd12240d332/internal/fakecgo/abi_amd64.h (about)

     1  // Copyright 2021 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // Macros for transitioning from the host ABI to Go ABI0.
     6  //
     7  // These save the frame pointer, so in general, functions that use
     8  // these should have zero frame size to suppress the automatic frame
     9  // pointer, though it's harmless to not do this.
    10  
    11  #ifdef GOOS_windows
    12  
    13  // REGS_HOST_TO_ABI0_STACK is the stack bytes used by
    14  // PUSH_REGS_HOST_TO_ABI0.
    15  #define REGS_HOST_TO_ABI0_STACK (28*8 + 8)
    16  
    17  // PUSH_REGS_HOST_TO_ABI0 prepares for transitioning from
    18  // the host ABI to Go ABI0 code. It saves all registers that are
    19  // callee-save in the host ABI and caller-save in Go ABI0 and prepares
    20  // for entry to Go.
    21  //
    22  // Save DI SI BP BX R12 R13 R14 R15 X6-X15 registers and the DF flag.
    23  // Clear the DF flag for the Go ABI.
    24  // MXCSR matches the Go ABI, so we don't have to set that,
    25  // and Go doesn't modify it, so we don't have to save it.
    26  #define PUSH_REGS_HOST_TO_ABI0()	\
    27  	PUSHFQ			\
    28  	CLD			\
    29  	ADJSP	$(REGS_HOST_TO_ABI0_STACK - 8)	\
    30  	MOVQ	DI, (0*0)(SP)	\
    31  	MOVQ	SI, (1*8)(SP)	\
    32  	MOVQ	BP, (2*8)(SP)	\
    33  	MOVQ	BX, (3*8)(SP)	\
    34  	MOVQ	R12, (4*8)(SP)	\
    35  	MOVQ	R13, (5*8)(SP)	\
    36  	MOVQ	R14, (6*8)(SP)	\
    37  	MOVQ	R15, (7*8)(SP)	\
    38  	MOVUPS	X6, (8*8)(SP)	\
    39  	MOVUPS	X7, (10*8)(SP)	\
    40  	MOVUPS	X8, (12*8)(SP)	\
    41  	MOVUPS	X9, (14*8)(SP)	\
    42  	MOVUPS	X10, (16*8)(SP)	\
    43  	MOVUPS	X11, (18*8)(SP)	\
    44  	MOVUPS	X12, (20*8)(SP)	\
    45  	MOVUPS	X13, (22*8)(SP)	\
    46  	MOVUPS	X14, (24*8)(SP)	\
    47  	MOVUPS	X15, (26*8)(SP)
    48  
    49  #define POP_REGS_HOST_TO_ABI0()	\
    50  	MOVQ	(0*0)(SP), DI	\
    51  	MOVQ	(1*8)(SP), SI	\
    52  	MOVQ	(2*8)(SP), BP	\
    53  	MOVQ	(3*8)(SP), BX	\
    54  	MOVQ	(4*8)(SP), R12	\
    55  	MOVQ	(5*8)(SP), R13	\
    56  	MOVQ	(6*8)(SP), R14	\
    57  	MOVQ	(7*8)(SP), R15	\
    58  	MOVUPS	(8*8)(SP), X6	\
    59  	MOVUPS	(10*8)(SP), X7	\
    60  	MOVUPS	(12*8)(SP), X8	\
    61  	MOVUPS	(14*8)(SP), X9	\
    62  	MOVUPS	(16*8)(SP), X10	\
    63  	MOVUPS	(18*8)(SP), X11	\
    64  	MOVUPS	(20*8)(SP), X12	\
    65  	MOVUPS	(22*8)(SP), X13	\
    66  	MOVUPS	(24*8)(SP), X14	\
    67  	MOVUPS	(26*8)(SP), X15	\
    68  	ADJSP	$-(REGS_HOST_TO_ABI0_STACK - 8)	\
    69  	POPFQ
    70  
    71  #else
    72  // SysV ABI
    73  
    74  #define REGS_HOST_TO_ABI0_STACK (6*8)
    75  
    76  // SysV MXCSR matches the Go ABI, so we don't have to set that,
    77  // and Go doesn't modify it, so we don't have to save it.
    78  // Both SysV and Go require DF to be cleared, so that's already clear.
    79  // The SysV and Go frame pointer conventions are compatible.
    80  #define PUSH_REGS_HOST_TO_ABI0()	\
    81  	ADJSP	$(REGS_HOST_TO_ABI0_STACK)	\
    82  	MOVQ	BP, (5*8)(SP)	\
    83  	LEAQ	(5*8)(SP), BP	\
    84  	MOVQ	BX, (0*8)(SP)	\
    85  	MOVQ	R12, (1*8)(SP)	\
    86  	MOVQ	R13, (2*8)(SP)	\
    87  	MOVQ	R14, (3*8)(SP)	\
    88  	MOVQ	R15, (4*8)(SP)
    89  
    90  #define POP_REGS_HOST_TO_ABI0()	\
    91  	MOVQ	(0*8)(SP), BX	\
    92  	MOVQ	(1*8)(SP), R12	\
    93  	MOVQ	(2*8)(SP), R13	\
    94  	MOVQ	(3*8)(SP), R14	\
    95  	MOVQ	(4*8)(SP), R15	\
    96  	MOVQ	(5*8)(SP), BP	\
    97  	ADJSP	$-(REGS_HOST_TO_ABI0_STACK)
    98  
    99  #endif